The invention relates to a battery unit comprising a plurality of electrically interconnected electrochemical cells that comprise in each case an electrode assembly having a cathode contact element and an anode contact element, and an outer sheath that encompasses an arrangement chamber in which the electrochemical cells are arranged.
Furthermore, the invention relates to a battery module having a plurality of electrically interconnected battery units.
Battery cells having a plurality of electrically interconnected electrochemical cells are known in different embodiments in the prior art. Furthermore, battery modules are known that comprise a plurality of interconnected battery cells as electrochemical cells. It is preferred that lithium ion cells are used as battery cells in particular owing to the high energy density.
Lithium ion cells can be embodied in particular as so-called round cells, as prismatic cells or as so-called pouch cells. The lithium ion cells comprise an electrode assembly having a cathode contact element and an anode contact element. Cylindrical cell wraps (jelly rolls) in particular are known as an electrode assembly for round cells, prismatic flat wraps for prismatic cells and so-called cell stacks. Such an electrode assembly comprises a cathode material, an anode material, a separator and an electrolyte.
Disadvantages in the case of battery units and battery modules known in the prior art are associated in particular with the interconnection of the electrochemical cells, with the size of the battery units and battery modules, above all with the battery units or battery modules that are to be used in hybrid vehicles, plug-in-hybrid vehicles or electric vehicles and are associated with the variability of battery units and battery modules with regard to their being adapted to suit different demands that are placed on a battery unit or a battery module by way of example with respect to the capacity to be provided and/or the performance.
It follows from this that it is an object of the invention to provide a battery unit that is improved with regard to the above mentioned disadvantages and also to provide an improved battery module. In particular, a battery unit is to be provided that comprises a higher energy density, in other words a battery unit that whilst maintaining the same capacity and performance of a conventional battery unit is smaller in size and thus requires less installation space.